The present invention relates to a remote copy technique duplicating data stored in a storage system to another storage system.
As a technique preventing data loss in a storage system due to disaster, there is a technique duplicating data to a storage system at a remote site (remote copy). Here, the storage system includes a storage device such as a disk and a storage controller coupled to the storage device for controlling input and output of data to/from the storage device. The remote copy is a technique in which a storage system at a primary site (hereinafter, also called a primary storage system) transfers data in the source storage system to another storage system (hereinafter, also called a secondary storage system) at a remote site (hereinafter, also called a secondary site), and the target storage system stores the data received from the source storage system in a storage device in the target storage system. As for the remote copy, disclosed is a technique duplicating data not via a host computer (hereinafter, called a host) between different storage controllers (see Patent Document 1).
Here, Patent Document 1 refers to U.S. Pat. No. 6,408,370.